find the element of an array

[pagheca]

Hi,

I'm looking for the simplest way to find the index of the element of a vector that is closer to a given value.

Suppose the vector is f[i:=i^2 and the value V:40 .

The solution is i=6 as 6^2=36. How to find that i value? Do there is any function doing that? Do you know any trick using the programming?

See attachment for an attempt to solve it (not working.

regards and thanks in advance

 

[pstuckey]

You can do this without programming. Using the variables in your sheet:

Error:= vectorize abs(f-v.LO)
Index:= match(min(Error),Error)

Vectorize is a function on the matrix toolbar.

Peter

 

[pagheca]

thanks very much, Peter. A very smart solution.
However, the result is a vector itself. How to convert it to a number?

Thanks again!

 

[pagheca]

got it: I have to specify the index, of course... I was confused by the fact it was a one element vector!

Thanks again.